Vonage
Communications APIs and CPaaS (formerly Nexmo).
API products
Vonage Messages API (WhatsApp)
"The Vonage Messages API integrates with SMS, MMS, RCS, WhatsApp, Messenger, Viber, and Email allowing you to communicate with your customers on the channels they like." - Vonage Messages API enables businesses to send and receive WhatsApp messages via a unified multichannel messaging platform.
Vonage SMS API
Our SMS API helps you create customer journeys through conversations - even within the context of your app.